Image displaying device and method, and image processing device and method

ABSTRACT

It is an object to prevent the image quality deterioration of a moving image likely to include a plurality of the same consecutive images such as a movie video and an animation video due to the motion-compensated frame rate conversion (FRC) processing. An image displaying device is provided with an FRC portion ( 10 ) for converting the number of frames in an input image signal by interpolating an image signal to which a motion compensation processing has been given between the frames in the input image signal, a genre determining portion ( 14 ) for determining whether the input image signal is a predetermined genre, and a controlling portion ( 15 ). The FRC portion ( 10 ) includes a motion vector detecting portion ( 11   e ) for detecting a motion vector between the frames of the input image signal, an interpolating vector evaluating portion ( 11   f ) for allocating an interpolating vector between the frames based on the motion vector information, and an interpolating frame generating portion ( 102 ) for generating an interpolating frame from the interpolating vector. In the case that the input image signal is relating to a movie or animation, the control portion ( 15 ) set the motion vector detected by the motion vector detecting portion ( 11   e ) to zero-vector to make the motion compensation processing of the FRC portion ( 10 ) ineffective.

TECHNICAL FIELD

The present invention relates to an image displaying device and methodand an image processing device and method having a function ofconverting a frame rate or field rate, and more particularly, to animage displaying device and an image displaying method of the device andan image processing device and an image processing method of the device,which include preventing the image quality deterioration of a movingimage likely to include a plurality of the same consecutive images dueto a motion-compensated rate conversion processing.

BACKGROUND OF THE INVENTION

As compared to conventional cathode-ray tubes (CRTs) primarily used forrealizing moving images, LCDs (Liquid Crystal Displays) have a drawback,so-called motion blur, which is the blurring of outline of a movingportion perceived by a viewer when displaying a moving image. It ispointed out that this motion blur arises from the LCD display modeitself (see, e.g., Specification of Japanese Patent No. 3295437;“Ishiguro Hidekazu and Kurita Taiichiro, “Consideration on MotionPicture Quality of the Hold Type Display with an octuple-rate CRT”,IEICE Technical Report, Institute of Electronics, Information andCommunication Engineers, EID96-4 (1996-06), p. 19-26”).

Since fluorescent material is scanned by an electron beam to causeemission of light for display in CRTs, the light emission of pixels isbasically impulse-like although slight afterglow of the fluorescentmaterial exists. This is called an impulse display mode. On the otherhand, in the case of LCDs, an electric charge is accumulated by applyingan electric field to liquid crystal and is retained at a relatively highrate until the next time the electric field is applied. Especially, inthe case of the TFT mode, since a TFT switch is provided for each dotcomposing a pixel and each pixel normally has an auxiliary capacity, theability to retain the accumulated charge is extremely high. Therefore,the light emission is continued until the pixels are rewritten by theapplication of the electric field based on the image information of thenext frame or field (hereinafter, represented by the frame). This iscalled a hold display mode.

Since the impulse response of the image displaying light has a temporalspread in the above hold display mode, spatial frequency characteristicsdeteriorate along with temporal frequency characteristics, resulting inthe motion blur. Since the human eye can smoothly follow a movingobject, if the light emission time is long as in the case of the holdtype, the movement of image seems jerky and unnatural due to the timeintegration effect.

To improve the motion blur in the above hold display mode, a frame rate(number of frames) is converted by interpolating an image between framesin a known technology. This technology is called FRC (Frame RateConverter) and is put to practical use in liquid crystal displayingdevices, etc.

Conventionally known methods of converting the frame rate includevarious techniques such as simply repeating read-out of the same framefor a plurality of times and frame interpolation using linearinterpolation between frames (see, e.g., Yamauchi Tatsuro, “TV StandardsConversion”, Journal of the Institute of Television Engineers of Japan,Vol. 45, No. 12, pp. 1534-1543 (1991)). However, in the case of theframe interpolation processing using the linear interpolation,unnaturalness of motion (jerkiness, judder) is generated due to theframe rate conversion, and the motion blur disturbance due to the abovehold display mode cannot sufficiently be improved, resulting ininadequate image quality.

To eliminate effects of the jerkiness, etc., and improve quality ofmoving images, a motion-compensated frame interpolation processing usingmotion vectors is proposed. Since a moving image itself is captured tocompensate the image movement in this processing, highly natural movingimages may be acquired without deteriorating the resolution andgenerating the jerkiness. Since interpolation image signals aregenerated with motion compensation, the motion blur disturbance due tothe above hold display mode may sufficiently be improved.

Above Specification of Japanese Patent No. 3295437 discloses atechnology of motion-adaptively generating interpolating frames toincrease a frame frequency of a display image for improvingdeterioration of spatial frequency characteristics causing the motionblur. In this case, at least one interpolation image signal interpolatedbetween frames of a display image is motion-adaptively created from theprevious and subsequent frames, and the created interpolation imagesignals are interpolated between the frames and are sequentiallydisplayed.

FIG. 1 is a block diagram of a schematic configuration of an FRC drivedisplay circuit in a conventional liquid crystal displaying device and,in FIG. 1, the FRC drive display circuit includes an FRC portion 100that converts the number of frames of the input image signal byinterpolating the image signals to which the motion compensationprocessing has been given between frames of the input video signal, anactive-matrix liquid crystal display panel 104 having a liquid crystallayer and an electrode for applying the scan signal and the data signalto the liquid crystal layer, and an electrode driving portion 103 fordriving a scan electrode and a data electrode of the liquid crystaldisplay panel 104 based on the image signal subjected to the frame rateconversion by the FRC portion 100.

The FRC portion 100 includes a motion vector detecting portion 101 thatdetects motion vector information from the input image signal and aninterpolating frame generating portion 102 that generates interpolatingframes based on the motion vector information acquired by the motionvector detecting portion 101.

In the above configuration, for example, the motion vector detectingportion 101 may obtain the motion vector information with the use of ablock matching method and a gradient method described later or if themotion vector information is included in the input image signal in someform, this information may be utilized. For example, the image datacompression-encoded with the use of the MPEG format includes motionvector information of a moving image calculated at the time of encoding,and this motion vector information may be acquired.

FIG. 2 is a diagram for explaining a frame rate conversion processing bythe conventional FRC drive display circuit shown in FIG. 1. The FRCportion 100 generates interpolating frames (gray-colored images in FIG.2) between frames with the motion compensation using the motion vectorinformation output from the motion vector detecting portion 101 andsequentially outputs the generated interpolation signals along with theinput frame signals to perform processing of converting the frame rateof the input image signal from 60 frames per second (60 Hz) to 120frames per second (120 Hz).

FIG. 3 is a diagram for explaining an interpolating frame generationprocessing of the motion vector detecting portion 101 and theinterpolating frame generating portion 102. The motion vector detectingportion 101 uses the gradient method to detect a motion vector 105 from,for example, a frame #1 and a frame #2 shown in FIG. 3. The motionvector detecting portion 101 obtains the motion vector 105 by measuringa direction and an amount of movement in 1/60 second between the frame#1 and the frame #2. The interpolating frame generating portion 102 thenuses the obtained motion vector 105 to allocate an interpolating vector106 between the frame #1 and the frame #2. An interpolating frame 107 isgenerated by moving an object (in this case, an automobile) from aposition of the frame #1 to a position after 1/120 second based on theinterpolating vector 106.

By performing the motion-compensated frame interpolation processing withthe use of the motion vector information to increase a display framefrequency in this way, the display state of the LCD (the hold displaymode) can be made closer to the display state of the CRT (the impulsedisplay mode) and the image quality deterioration can be improved whichis due to the motion blur generated when displaying a moving image.

In the motion-compensated frame interpolation processing, it isessential to detect the motion vectors for performing the motioncompensation. For example, the block matching method and the gradientmethod are proposed as representative techniques for the motion vectordetection. In these methods, the motion vector is detected for eachpixel or small block between two consecutive frames and this motionvector is used to interpolate each pixel or small block of theinterpolating frame between two frames. An image at an arbitraryposition between two frames is interpolated at an accurately compensatedposition to convert the number of frames.

Since the frames are highly correlated in moving images and hascontinuity in the time axis direction, a pixel or a small block movingin one frame tends to move with the same movement amount in thesubsequent frame or the previous frame. For example, in the case of amoving image of a ball rolling from the right to the left of a screen,the ball area moves with similar movement amounts in every frame.Consecutive frames tend to have the continuity of motion vectors.

Therefore, the motion vector in the next frame may more easily or moreaccurately be detected by reference to a motion vector detection resultof preceding frames. For example, in the iterative gradient method,which is an improved gradient method, a motion vector of a neighboringblock already detected in the previous frame or the current frame isdefined as an initial deflection vector, which is used as a startingpoint to repeat calculations of the gradient method for a detectedblock. With this method, a substantially accurate movement amount can beacquired by repeating the gradient method about two times.

A motion vector may also efficiently be detected in the block matchingmethod in such a way that a reference is made to the motion vectordetection result of the previous frame to change the search order. Whendetecting a motion vector, for example, the frame rate conversion may beprocessed in real time by utilizing the motion vector already detected.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

Video signals may be sourced from videos from movie films and videosfrom computer graphics (CG) in addition to videos shot by normaltelevision video cameras. Therefore, television broadcast signals andvideo disc reproduction signals in the NTSC mode or the PAL mode ofteninclude video signals from movie films or CG. Due to the recentdevelopment in storage capacity of recording medium (e.g., DVD (digitalversatile disc), HD (hard disc)) and the digitization of transmissionmethods, video signals from various sources may be mixed.

For example, a normal movie film has 24 frames per second and, when thisfilm is output to a display having a frame rate of 60 Hz, the videohaving a frame rate of 24 Hz is to which the 2-3 pull-down processinghas been given and is converted into and output as video signals havinga frame rate of 60 Hz by outputting the same images for every two orthree frames.

When a film movie or a CG animation video having 30 frames per second isoutput to a display having a frame rate of 60 Hz, the video having aframe rate of 30 Hz is subjected to the 2-2 pull-down processing and isconverted into and output as video signals having a frame rate of 60 Hzby outputting the same images for every two frames. When a film moviehaving 24 frames per second is output to a display having a frame rateof 50 Hz, the video having a frame rate of 24 Hz is to which the 2-2pull-down processing has been given and the same images are output forevery two frames.

Film movies or CG animation videos often have original images having aframe rate equal to 60 Hz or less and are displayed and output as 60-Hzvideo signals by consecutively outputting a plurality of the same imagesas above.

The case of a film movie having 24 frames per second described abovewill be described with reference to FIG. 4. Frame #1 to #10 of FIG. 4represents an image sequence converted into 60 Hz from a 24-Hz movievideo through the 2-3 pull-down processing. The frames #1 and #2, theframes #3 to #5, the frames #6 and #7, and the frames #8 to #10 are thesame images, respectively.

In a video likely to include a plurality of the same output images, thecontinuity of motion vectors becomes impaired between frames. Forexample, it is assumed that some kind of a moving object is shot in thevideo of FIG. 4. Although a motion vector is detected between the frames#5 and #6 since these frames are different images, a motion vector to bedetected should completely be zero between the next frames #6 and #7since these frames are the same images. Since the next frames #7 and #8are different images, a motion vector is detected between these frames.

With regard to the motion vectors of the successive frames from theframe #5 to the frame #7 of FIG. 4, no continuity of the motion vectorsexists between adjacent frames since “motion vector exists”, “motionvector is zero”, and “motion vector exists” are mixed in this order.

If the processing for detecting the motion vector in the next frame isexecuted by referring to the motion vector detection result of theprevious frame as above for such a video likely to include a pluralityof the same output images, it is problematic that the motion vector iserroneously detected since no continuity of the motion vector existsbetween the frames.

In the above example, although a motion vector to be detected shouldcompletely be zero between the frames #6 and #7 since these frames arethe same images, a motion vector between the previous frames #5 and #6is not zero and, therefore, a vector other than zero may erroneously bedetected by referring to this vector.

Although a motion vector should be detected between the frames #7 and #8since these frames are different images, a motion vector between theprevious frames #6 and #7 is zero and, therefore, a zero vector mayerroneously be detected by referring to this vector. It is problematicthat such an erroneous detection of the motion vector may cause theimage quality deterioration in the displayed video.

The present invention was conceived in view of the above problems and itis therefore the object of the present invention to provide an imagedisplaying device and method and an image processing device and methodcapable of preventing the image quality deterioration of a moving imagelikely to include a plurality of the same consecutive images such as amovie video and an animation video due to the motion-compensated framerate conversion (FRC) processing.

Means for Solving the Problems

A first invention of the present application is an image displayingdevice having a rate converting portion that interpolates aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein a determining portion that determines a content genrethe input image signal belongs to based on genre information acquiredfrom broadcast data, a medium, or a network is included and the rateconverting portion includes an interpolation image generating portionthat applies a motion compensation processing to the input image signalto generate an interpolation image signal based on motion vectorinformation between frames or fields of the input image signal, and theimage signal generated by applying the motion compensation processing isnot interpolated when the genre determined by the determining portion isa certain genre including a moving image potentially having the sameconsecutive images in a plurality of frames or fields.

A second invention of the present application is an image displayingdevice, wherein the rate converting portion interpolates an image signalgenerated by disabling the motion compensation processing of theinterpolation image generating portion between frames or fields of theinput image signal when the genre determined by the determining portionis the certain genre.

A third invention of the present application is an image displayingdevice, wherein the interpolation image generating portion includes amotion vector detecting portion that detects the motion vectorinformation between consecutive frames or fields included in the inputimage signal, and an interpolating vector allocating portion thatallocates an interpolating vector between the frames or the fields basedon the detected motion vector information.

A fourth invention of the present application is an image displayingdevice, wherein the interpolation image generating portion sets themotion vector detected by the motion vector detecting portion tozero-vector to make the motion compensation processing ineffective whenthe genre determined by the determining portion is the certain genre.

A fifth invention of the present application is an image displayingdevice, wherein the interpolation image generating portion sets theinterpolating vector allocated by the interpolating vector allocatingportion to zero-vector to make the motion compensation processingineffective when the genre determined by the determining portion is thecertain genre.

A sixth invention of the present application is an image displayingdevice, wherein the image displaying device does not insert theinterpolation image signal generated by applying the motion compensationprocessing between frames or fields of the input image signal and doesnot convert the number of frames or fields of the input image signalwhen the genre determined by the determining portion is the certaingenre.

A seventh invention of the present application is an image displayingdevice, wherein a drive frequency of a display panel displaying theimage signals is variable, and the image displaying device includes aportion for varying the drive frequency of the display panel from aframe frequency or a field frequency converted by the rate convertingportion to a frame frequency or a field frequency of the input imagesignal when the genre determined by the determining portion is thecertain genre.

An eighth invention of the present application is an image displayingdevice, wherein the rate converting portion inserts an image signal towhich the motion compensation processing has not been given betweenframes or fields of the input image signal to convert the number offrames or fields of the input image signal when the genre determined bythe determining portion is the certain genre.

A ninth invention of the present application is an image displayingdevice, wherein the rate converting portion inserts between frames orfields of the input image signal an image signal of the frames or thefields to convert the number of frames or fields of the input imagesignal when the genre determined by the determining portion is thecertain genre.

A tenth invention of the present application is an image displayingdevice, wherein the rate converting portion interpolates between framesor fields of the input image signal an image signal acquired by applyinga linear interpolation processing to an image signal of the frames orthe fields to convert the number of frames or fields of the input imagesignal when the genre determined by the determining portion is thecertain genre.

An eleventh invention of the present application is an image displayingdevice, wherein the rate converting portion inserts a predeterminedmonochromatic image signal between frames or fields of the input imagesignal to convert the number of frames or fields of the input imagesignal when the genre determined by the determining portion is thecertain genre.

A twelfth invention of the present application is an image displayingdevice, wherein the certain genre is movie.

A thirteenth invention of the present application is an image displayingdevice, wherein the certain genre is animation.

A fourteenth invention of the present application is an image displayingdevice, wherein the determining portion determines the genre of contentsthe input image signal belongs to based on electronic programinformation transmitted by superimposing on broadcast data.

A fifteenth invention of the present application is an image displayingdevice, wherein the determining portion determines the genre of contentsthe input image signal belongs to based on identification informationwhich is indicative of the contents and is added to a medium.

A sixteenth invention of the present application is an image displayingdevice, wherein the rate converting portion converts a frame frequencyor field frequency of the input image signal into integral multiples ofeach of them.

A seventeenth invention of the present application is an imagedisplaying method having a rate converting step of interpolating aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the step of determining a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is included and the rate converting stepincludes an interpolation image generating step of applying a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and the image signalgenerated by applying the motion compensation processing is notinterpolated when the determined genre is a certain genre including amoving image potentially having the same consecutive images in aplurality of frames or fields.

An eighteenth invention of the present application is an imagedisplaying method, wherein at the rate converting step, an image signalgenerated by making the motion compensation processing at theinterpolation image generating step ineffective is interpolated betweenframes or fields of the input image signal when the determined genre isthe certain genre.

A nineteenth invention of the present application is an image displayingmethod, wherein the interpolation image signal generated by applying themotion compensation processing is not inserted between frames or fieldsof the input image signal and the number of frames or fields of theinput image signal is not converted when the determined genre is thecertain genre.

A twentieth invention of the present application is an image displayingmethod, wherein at the rate converting step, an image signal of theframes or the fields is inserted between frames or fields of the inputimage signal to convert the number of frames or fields of the inputimage signal when the determined genre is the certain genre.

A twenty-first invention of the present application is an imagedisplaying method, wherein at the rate converting step, an image signalacquired by applying a linear interpolation processing to an imagesignal of the frames or the fields is interpolated between frames orfields of the input image signal to convert the number of frames orfields of the input image signal when the determined genre is thecertain genre.

A twenty-second invention of the present application is an imagedisplaying method, wherein at the rate converting step, a predeterminedmonochromatic image signal is inserted between frames or fields of theinput image signal to convert the number of frames or fields of theinput image signal when the determined genre is the certain genre.

A twenty-third invention of the present application is an imageprocessing device having a rate converting portion that interpolates aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the rate converting portion includes an interpolationimage generating portion that applies a motion compensation processingto the input image signal to generate an interpolation image signalbased on motion vector information between frames or fields of the inputimage signal, and the image signal generated by applying the motioncompensation processing is not interpolated when the genre determined bya determining portion that determines a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is a certain genre potentially including animage signal having the same consecutive images in a plurality of framesor fields.

A twenty-fourth invention of the present application is an imageprocessing device, wherein the rate converting portion interpolates animage signal generated by making the motion compensation processing ofthe interpolation image generating portion ineffective between frames orfields of the input image signal when the genre determined by thedetermining portion is the certain genre.

A twenty-fifth invention of the present application is an imageprocessing device, wherein the rate converting portion inserts an imagesignal to which the motion compensation processing has not been givenbetween frames or fields of the input image signal to convert the numberof frames or fields of the input image signal when the genre determinedby the determining portion is the certain genre.

A twenty-sixth invention of the present application is an imageprocessing method having a rate converting step of interpolating aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the step of determining a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is included and the rate converting stepincludes an interpolation image generating step of applying a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and the image signalgenerated by applying the motion compensation processing is notinterpolated when the determined genre is a certain genre including amoving image potentially having the same consecutive images in aplurality of frames or fields.

A twenty-seventh invention of the present application is an imagedisplaying method, wherein at the rate converting step, an image signalgenerated by making the motion compensation processing at theinterpolation image generating step ineffective is interpolated betweenframes or fields of the input image signal when the determined genre isthe certain genre.

A twenty-eighth invention of the present application is an imagedisplaying method, wherein at the rate converting step, an image signalof the frames or the fields is inserted between frames or fields of theinput image signal to convert the number of frames or fields of theinput image signal when the determined genre is the certain genre.

A twenty-ninth invention of the present application is an imagedisplaying method, wherein at the rate converting step, an image signalacquired by applying a linear interpolation processing to an imagesignal of the frames or the fields is interpolated between frames orfields of the input image signal to convert the number of frames orfields of the input image signal when the determined genre is thecertain genre.

A thirtieth invention of the present application is an image displayingmethod, wherein at the rate converting step, a predeterminedmonochromatic image signal is inserted between frames or fields of theinput image signal to convert the number of frames or fields of theinput image signal when the determined genre is the certain genre.

A thirty-first invention of the present application is an imagedisplaying device having a rate converting portion that interpolates aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein a determining portion that determines a content genrethe input image signal belongs to based on genre information acquiredfrom broadcast data, a medium, or a network is included and the rateconverting portion includes an interpolation image generating portionthat applies a motion compensation processing to the input image signalto generate an interpolation image signal based on motion vectorinformation between frames or fields of the input image signal, and theinterpolation image signal generated by reducing a compensationintensity of the motion compensation processing is interpolated betweenframes or fields of the input image signal when the genre determined bythe determining portion is a certain genre includes a moving imagepotentially having the same consecutive images in a plurality of framesor fields.

A thirty-second invention of the present application is an imagedisplaying device, wherein the interpolation image generating portionperforms weighted addition of an image signal to which the motioncompensation processing has been given and an image signal to which themotion compensation processing has not been given at a predeterminedrate to generate an interpolation image signal, and the weightedaddition rate is varied when the genre determined by the determiningportion is the certain genre.

A thirty-third invention of the present application is an imagedisplaying device, wherein the interpolation image generating portionuses the image signal to which the motion compensation processing hasnot been given for the interpolation image signal when the genredetermined by the determining portion is the certain genre and uses theimage signal to which the motion compensation processing has been givenfor the interpolation image signal when the genre determined by thedetermining portion is not the certain genre.

A thirty-fourth invention of the present application is an imagedisplaying device, wherein the interpolation image generating portionuses an image signal to which a linear interpolation processing has beengiven between frames or fields of the input image signal as the imagesignal to which the motion compensation processing has not been given.

A thirty-fifth invention of the present application is an imagedisplaying device, wherein the certain genre is movie.

A thirty-sixth invention of the present application is an imagedisplaying device, wherein the certain genre is animation Athirty-seventh invention of the present application is an imagedisplaying device, wherein the determining portion determines the genreof contents the input image signal belongs to based on electronicprogram information transmitted by superimposing on broadcast data.

A thirty-eighth invention of the present application is an imagedisplaying device, wherein the determining portion determines the genreof contents the input image signal belongs to based on identificationinformation which is indicative of the contents and is added to amedium.

A thirty-ninth invention of the present application is an imagedisplaying method having a rate converting step of interpolating aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the step of determining a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is included and the rate converting stepincludes an interpolation image generating step of applying a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and an interpolation imagesignal generated by reducing a compensation intensity of the motioncompensation processing is interpolated between frames or fields of theinput image signal when the determined genre is a certain genreincluding a moving image potentially having the same consecutive imagesin a plurality of frames or fields.

A fortieth invention of the present application is an image processingdevice having a rate converting portion that interpolates aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the rate converting portion includes an interpolationimage generating portion that applies a motion compensation processingto the input image signal to generate an interpolation image signalbased on motion vector information between frames or fields of the inputimage signal, and the interpolation image signal generated by reducing acompensation intensity of the motion compensation processing isinterpolated between frames or fields of the input image signal when thegenre determined by a determining portion that determines a contentgenre the input image signal belongs to based on genre informationacquired from broadcast data, a medium, or a network is a certain genreincluding a moving image potentially having the same consecutive imagesin a plurality of frames or fields.

A forty-first invention of the present application is an imageprocessing method having a rate converting step of interpolating aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the step of determining a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is included and the rate converting stepincludes an interpolation image generating step of applying a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and an interpolation imagesignal generated by reducing a compensation intensity of the motioncompensation processing is interpolated between frames or fields of theinput image signal when the determined genre is a certain genreincluding a moving image potentially having the same consecutive imagesin a plurality of frames or fields.

Effects of the Invention

According to the present invention, the image quality deterioration ofdisplayed images may effectively be prevented by not executing theinterpolation processing through motion compensation or by reducing thecompensation intensity of the motion compensation process if imagesignals of certain predetermined genres are input.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram of a schematic configuration of an FRC drivedisplay circuit in a conventional liquid crystal displaying device.

FIG. 2 is a diagram for explaining a frame rate conversion processing bythe conventional FRC drive display circuit shown in FIG. 1.

FIG. 3 is a diagram for explaining an interpolating frame generationprocessing of a motion vector detecting portion and an interpolatingframe generating portion.

FIG. 4 is a diagram for explaining an image sequence when a 24-Hz filmmovie is converted by the 2-3 pull-down processing into 60 Hz.

FIG. 5 is a block diagram of an exemplary configuration of a frame rateconverting portion included in an image displaying device of the presentinvention.

FIG. 6 is a diagram for explaining an example of an interpolating framegenerating processing of a frame generating portion.

FIG. 7 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to a first embodiment of the presentinvention.

FIG. 8 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to a second embodiment of thepresent invention.

FIG. 9 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to a third embodiment of the presentinvention.

FIG. 10 is a diagram of a relationship between input data and outputdata according to the third embodiment of the present invention.

FIG. 11 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to a fourth embodiment of thepresent invention.

FIG. 12 is a diagram of a relationship between input data and outputdata according to the fourth embodiment of the present invention.

FIG. 13 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to a fifth embodiment of thepresent invention.

FIG. 14 is a diagram of a relationship between input data and outputdata according to the fifth embodiment of the present invention.

FIG. 15 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to a sixth embodiment of thepresent invention.

FIG. 16 is a diagram of a relationship between input data and outputdata according to the sixth embodiment of the present invention.

FIG. 17 is a block diagram of an exemplary main configuration of an FRCportion according to a seventh embodiment of the present invention.

FIG. 18 is a flowchart for explaining an example of an image displayingmethod by the image displaying device of the present invention.

FIG. 19 is a flowchart for explaining another example of the imagedisplaying method by the image displaying device of the presentinvention.

FIG. 20 is a flowchart for explaining another example of the imagedisplaying method by the image displaying device of the presentinvention.

EXPLANATIONS OF REFERENCE NUMERALS

10, 100 . . . frame rate converting (FRC) portion; 11 . . . vectordetecting portion; 11 a . . . luminance signal extracting portion; 11 b. . . preprocessing filter; 11 c . . . motion detection frame memory; 11d . . . initial vector memory; 11 e, 101 . . . motion vector detectingportion; 11 f . . . interpolating vector evaluating portion; 12 . . .frame generating portion; 12 a . . . interpolating frame memory; 12 b,102 . . . interpolating frame generating portion; 12 c . . . time baseconversion frame memory; 12 d . . . time base converting portion; 12 e .. . compensation intensity varying portion; 14 . . . genre determiningportion; 15 . . . controlling portion; 16 . . . switching portion; 17 .. . zero vector; 18, 103 . . . electrode driving portion; 19, 104 . . .liquid crystal display panel; 20 . . . path; 21 . . . memory; 22 . . .linear interpolation processing portion; 23 . . . black-level signalinsert processing portion; 105 . . . motion vector; 106 . . .interpolating vector; and 107 . . . interpolating frame.

PREFERRED EMBODIMENT OF THE INVENTION

A preferred embodiment of an image displaying device of the presentinvention will now be described referring to the accompanying drawings.Although the present invention is applicable to either field signals andinterpolation field signals or frame signals and interpolating framesignals, the frame signals and the interpolating frame signals will bedescribed as a representative example since both (field and frame) arein a similar relationship with each other.

FIG. 5 is a block diagram of an exemplary configuration of a motioncompensated frame rate converting portion included in the imagedisplaying device of the present invention, in FIG. 5, reference numeral10 denotes a frame rate converting portion (hereinafter, FRC portion),and the FRC portion 10 corresponds to a rate converting portion of thepresent invention and is comprised of a vector detecting portion 11 thatdetects a motion vector between two consecutive frames included in aninput image signal and a frame generating portion 12 that generates aninterpolating frame (interpolation image) based on the detected motionvector. Although the iterative gradient method is used for the motionvector detection in the description of the vector detecting portion 11,the method is not limited to the iterative gradient method and may bethe block matching method.

A feature of the iterative gradient method is that several types ofmovement amounts may be detected, and a motion vector may be detectedeven from a moving object having a small region since a motion vectormay be detected for each block. The circuit configuration thereof may berealized in a smaller scale than other modes (such as the block matchingmethod). In the iterative gradient method, an already detected motionvector of a neighboring block is defined as an initial deflectionvector, which is used as a starting point to repeat calculations of thegradient method for a detected block. With this method, a substantiallyaccurate movement amount may be acquired by repeating the gradientmethod about two times.

In FIG. 5, the vector detecting portion 11 includes a luminance signalextracting portion 11 a that extracts a luminance signal (Y signal) froman input image signal (RGB signal), a preprocessing filter 11 b thatlimits a high bandwidth by applying LPF to the extracted Y signal, amotion detection frame memory 11 c, an initial vector memory 11 d thataccumulates initial vector candidates, a motion vector detecting portion11 e that detects motion vectors between frames with the use of theiterative gradient method, and an interpolating vector evaluatingportion 11 f that allocates an interpolating vector between the framesbased on the detected motion vectors.

The FRC portion 10 corresponds to the rate converting portion of thepresent invention; the motion vector detecting portion 11 e correspondsto a motion vector detecting portion of the present invention; and theinterpolating vector evaluating portion 11 f corresponds to aninterpolating vector allocating portion of the present invention.

Since a differential component of a pixel is used for the calculationsof the above iterative gradient method, the method is easily affected bynoises and calculation errors are increased if large gradient variationsexist in a detected block and, therefore, the LPF is applied by thepreprocessing filter 11 b to limit the high bandwidth. In the initialvector memory 11 d, motion vectors (initial vector candidates) alreadydetected in a frame immediately before the previous frame areaccumulated as initial vector candidates.

The motion vector detecting portion 11 e selects a motion vector closestto the motion vector of the detected block for an initial vector fromthe initial vector candidates accumulated in the initial vector memory11 d. The initial vector is selected by the block matching method fromthe already detected motion vectors (initial vector candidates) inneighboring blocks of the detected block. The motion vector detectingportion 11 e uses the selected initial vector as a starting point todetect a motion vector between a previous frame and a current framethrough the calculations of the gradient method.

The interpolating vector evaluating portion 11 f evaluates the motionvectors detected by the motion vector detecting portion 11 e, allocatesan optimum interpolating vector to an interpolation block between framesbased on the evaluation result, and outputs the vector to the framegenerating portion 12.

The frame generating portion 12 includes an interpolating frame memory12 a that accumulates two input frames (previous frame and currentframe), an interpolating frame generating portion 12 b that generates aninterpolating frame based on the two input frames from the interpolatingframe memory 12 a and the interpolating vector from the interpolatingvector evaluating portion 11 f, a time base conversion frame memory 12 cfor accumulating the input frames (previous frame and current frame),and a time base converting portion 12 d that inserts the interpolatingframe from the interpolating frame generating portion 12 b into theinput frames from the time base conversion frame memory 12 c to generatean output image signal (RGB signal).

The interpolating frame generating portion 12 b corresponds to aninterpolation image generating portion of the present invention and thetime base converting portion 12 d corresponds to an image interpolatingportion of the present invention.

FIG. 6 is a diagram for explaining an example of the interpolating framegenerating processing of the frame generating portion 12. Theinterpolating frame generating portion 12 b stretches an interpolatingvector V allocated to the interpolation block into the previous frameand the current frame and uses pixels located adjacent to theintersecting points with the frames to interpolate the pixels in theinterpolation block. For example, in the previous frame F₁, theluminance of a point A is calculated from three adjacent points. In thecurrent frame F₂, the luminance of a point B is calculated from threeadjacent points. In the interpolating frame F₁₂, the luminance of apoint P is interpolated using the luminance of the points A and B. Theluminance of the point P may be an average of the luminance of the pointA and the luminance of the point B, for example.

The interpolating frame F₁₂ generated as above is sent to the time baseconverting portion 12 d. The time base converting portion 12 dsandwiches the interpolating frame F₁₂ between the previous frame F₁ andthe current frame F₂ to perform processing of converting a frame rate.In this way, the FRC portion 10 may convert the input image signal (60frames/sec) into a motion-compensated output image signal (120frames/sec), which may be output to a display panel to reduce the motionblur and improve the moving image quality. Although the 60-frame/secinput image signal is converted into the 120-frame/sec (double) outputimage signal in the frame rate conversion of this description, this isobviously applicable to the case of acquiring 90-frame/sec (1.5 times)and 180-frame/sec (three times) output image signals, for example.

The image displaying device of the present invention includes the FRCportion 10 shown in FIG. 5 and the main object thereof is to make themotion compensation processing of the FRC portion 10 ineffective overthe entire screen (full screen) to prevent the image qualitydeterioration due to the FRC processing if the input image signals areimage signals likely to include a plurality of the same consecutiveimages such as a movie video and an animation video because of the 2-3pull-down processing or the 2-2 pull-down processing. Although thepresent invention is applicable to general image displaying deviceshaving the hold-type display characteristics such as liquid crystaldisplays, organic EL displays, and electrophoretic displays, arepresentative example described in the following embodiments will bethe case of applying the present invention to a liquid crystaldisplaying device using a liquid crystal display panel for a displaypanel.

In a first embodiment of the present invention, when the input imagesignal is an image signal of a certain genre, for example, movie oranimation, the output of the motion vector detecting portion 11 e isforced to be zero-vector to make the motion compensation processing ofthe FRC portion 10 ineffective.

FIG. 7 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to the first embodiment of thepresent invention and the liquid crystal displaying device includes theFRC portion 10, a genre determining portion 14, a controlling portion15, a switching portion 16, a zero-vector portion 17, an electrodedriving portion 18, and a liquid crystal display panel 19. The switchingportion 16 is disposed between the motion vector detecting portion 11 eand the interpolating vector evaluating portion 11 f within the FRCportion 10 and switches over the motion vector from the motion vectordetecting portion 11 e to the zero-vector 17 in accordance with theinstruction from the controlling portion 15.

The genre determining portion 14 determines a genre type of a videodisplayed on the liquid crystal display panel 19 based on genreinformation included in the EPG (Electronic Program Guide) dataseparated and extracted from broadcast data, for example. Although thegenre information may be included in a portion of the EPG datatransmitted by being superimposed on, for example, the broadcast data ofthe terrestrial digital broadcasting or BS/CS digital broadcasting, thiskind of information indicative of genre is not limited to beseparated/acquired from broadcast data and, for example, if videoinformation reproduced by an external device (such as a DVD player and aBlu-ray Disc player) is displayed, a flag representing contents (e.g.,an identification code indicative of “movie”) added to a medium may beread and detected by the genre determining portion 14.

The broadcast data is not limited to the digital broadcasting and thegenre information may also be acquired from analog broadcasting. Forexample, ADAMS-EPG is the EPG information transmitted by beingsuperimposed on the analog broadcasting.

The genre information of video contents may be input not onlyconcurrently with the input video data but also from a route other thanthe video data. For example, XMLTV is an application that automaticallyacquires a TV program table published on the Web to output the programtable in the XML format, and this may be utilized for acquiring thegenre information of the video to be displayed from a network.

For example, the genre code is prescribed as the genre information bythe terrestrial digital broadcasting standard for program genres of“news/report”, “sport”, “information/tabloid show”, “drama”, “music”,“variety”, “movie”, “animation/special effects”, “documentary/cultural”,“stage/performance”, “hobby/educational”, and “others” as majorcategories, and a plurality of middle categories is prescribed for eachmajor category.

The liquid crystal displaying device of the embodiment determines whichgenre the input image signal to be displayed belongs to and controls themotion compensation processing of the FRC portion 10 depending on thisdetermination result.

The liquid crystal display panel 19 is an active-matrix liquid crystaldisplay that has a liquid crystal layer and electrodes for applying scansignals and data signals to the liquid crystal layer. The electrodedriving portion 18 is a display driver for driving the scan electrodesand the data electrodes of the liquid crystal display panel 19 based onthe image signal to which the frame rate conversion by the FRC portion10 has been given. The controlling portion 15 includes a CPU forcontrolling the above portions and performs control such that the motioncompensation processing of the FRC portion 10 is made ineffective whenthe genre determining portion 14 determines that the input image signalis an image signal of a certain predetermined genre.

The drive frequency of the liquid crystal display panel 19 is a framefrequency converted by the FRC portion 10. Therefore, if an image signalinput with a frame frequency of 60 Hz is converted by the FRC portion 10into a frame frequency of 120 Hz, the drive frequency of the liquidcrystal display panel 19 is 120 Hz. However, if the frame frequencyconversion of the FRC processing is not performed and the input imagesignal is directly displayed and output, the drive frequency of theliquid crystal display panel 19 is the frame frequency of the inputimage signal.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 switches the switching portion 16 tothe zero-vector 17 to forcibly replace the motion vector detected by themotion vector detecting portion 11 e with the zero-vector. If the genredetermining portion 14 determines that the input image signal is animage signal of a genre other than the “movie” or “animation/specialeffects” genre, the switching portion 16 is switched to the motionvector detecting portion 11 e to input the motion vector detected by themotion vector detecting portion 11 e to the interpolating vectorevaluating portion 11 f.

Therefore, the moving image quality may be improved by themotion-compensated FRC processing at the time of the normal moving imagedisplay and, when a moving image such as movie or animation likely toinclude a plurality of the same consecutive images is input, thedetection errors, the motion compensation errors, etc., of the motionvector due to the discontinuity of the image movement are eliminated andthe image quality may effectively be prevented from deteriorating due tothe motion-compensated FRC processing by making the motion compensationprocessing ineffective with the motion vector set to zero-vector.

In a second embodiment of the present invention, when the input imagesignal is an image signal of a certain genre, for example, movie oranimation, the interpolating vector from the interpolating vectorevaluating portion 11 f is set to zero-vector to make the motioncompensation processing of the FRC portion 10 ineffective so that nointerpolation can occur between pixels located at different positions.

FIG. 8 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to the second embodiment of thepresent invention and the liquid crystal displaying device includes theFRC portion 10, the genre determining portion 14, the controllingportion 15, the switching portion 16, the zero-vector portion 17, theelectrode driving portion 18, and the liquid crystal display panel 19.The switching portion 16 is disposed between the interpolating vectorevaluating portion 11 f and the interpolating frame generating portion12 b within the FRC portion 10 and switches the interpolating vectorfrom the interpolating vector evaluating portion 11 f to the zero-vector17 in accordance with the instruction from the controlling portion 15.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 switches the switching portion 16 tothe zero-vector 17 to set the interpolating vector allocated by theinterpolating vector evaluating portion 11 f to zero-vector. If thegenre determining portion 14 determines that the input image signal isan image signal of a genre other than the “movie” or “animation/specialeffects” genre, the switching portion 16 is switched to theinterpolating vector evaluating portion 11 f to input the interpolatingvector allocated by the interpolating vector evaluating portion 11 f tothe interpolating frame generating portion 12 b.

When the moving image such as movie or animation likely to include aplurality of the same consecutive images is input, the detection errors,the motion compensation errors, etc., of the motion vector due to thediscontinuity of the image movement are eliminated in the same was asdescribed in the first embodiment and the image quality may effectivelybe prevented from deteriorating due to the motion-compensated FRCprocessing by making the motion compensation processing ineffective withthe interpolating vector forcibly set to zero-vector.

In a third embodiment of the present invention, a path is provided tobypass the FRC portion 10 and, when the input image signal is an imagesignal of a certain genre, for example, movie or animation, the inputimage signal is input to the bypass to change the drive frequency of theliquid crystal display panel 19 in conformity with the frame frequencyof the input image signal. If the image signal of contents of a certainpredetermined genre is input, the switching is performed such that theinput image signal is directly output and displayed on the liquidcrystal display panel 19 without performing the frame rate conversion.

FIG. 9 is a block diagram of an exemplary main configuration of a liquidcrystal displaying device according to the third embodiment of thepresent invention and the liquid crystal displaying device includes theFRC portion 10, the genre determining portion 14, the controllingportion 15, the switching portion 16, the electrode driving portion 18,the liquid crystal display panel 19, and a path 20 for bypassing the FRCportion 10. The switching portion 16 is disposed on the previous stageof the FRC portion 10 and switches the input image signal to inputwhether to the FRC portion 10 or to the path 20 in accordance with theinstruction from the controlling portion 15.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 shifts the switching portion 16 to thepath 20 to bypass the FRC portion 10. If the genre determining portion14 determines that the input image signal is an image signal of a genreother than the “movie” or “animation/special effects” genre, theswitching portion 16 is shifted to the FRC portion 10 to perform the FRCprocessing (motion-compensated frame interpolation processing) for theinput image signal. The switching portion 16 may be disposed on thesubsequent stage of the FRC portion 10 such that the output signal ofthe FRC portion 10 and the output signal of the path 20 are switchedover to output to the liquid crystal display panel 19.

In this embodiment, the controlling portion 15 may change the drivefrequency of the liquid crystal display panel 19, and if the imagesignal of the “movie” or “animation/special effects” genre is input, theinput image signal is input to the path 20 to change the drive frequencyof the liquid crystal display panel 19 in conformity with the framefrequency of the input image signal.

FIG. 10 is a diagram of a relationship between input data and outputdata according to the third embodiment of the present invention. FIG.10(A) depicts the input data to the path 20 and FIG. 10(B) depicts theoutput data from the path 20. As shown in FIG. 10(A), if the input imagesignal (input data) is input to the path 20 with a frame frequency of 60Hz, the display time per frame is about 16.7 ms. The controlling portion15 controls the electrode driving portion 18, which is the displaydriver, to change the drive frequency of the liquid crystal displaypanel 19 from 120 Hz to 60 Hz and causes the input data to be outputfrom the path 20 at 60 Hz without performing the frame rate conversionas shown in FIG. 10(B).

Since the liquid crystal display panel 19 displays the frame output fromthe path 20 without the frame rate conversion at the drive frequency of60 Hz, the display time per frame is still about 16.7 ms.

Therefore, the moving image quality may be improved by themotion-compensated FRC processing at the time of the normal moving imagedisplay and, when the moving image such as movie or animation likely toinclude a plurality of the same consecutive images is input, thedetection errors, the motion compensation errors, etc., of the motionvector due to the discontinuity of the image movement are eliminated andthe image quality may effectively be prevented from deteriorating due tothe motion-compensated FRC processing by prohibiting the frame rateconversion itself with the FRC processing bypassed.

In a fourth embodiment of the present invention, a path is provided tobypass the FRC portion 10 and, when the input image signal is an imagesignal of a certain genre, for example, movie or animation, the inputimage signal is input to the bypass to accumulate the input image signalin a memory on the path and the frame rate is converted by rapidly andrepeatedly reading the image signal of the same frame from the memorymore than once. If the image signal of contents of a certainpredetermined genre is input, the switching is performed such that theinput image signal is rapidly and sequentially output to convert theframe rate and is output and displayed on the liquid crystal displaypanel 19 without performing the motion-compensated frame rateconversion.

FIG. 11 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to the fourth embodiment ofthe present invention and the liquid crystal displaying device includesthe FRC portion 10, the genre determining portion 14, the controllingportion 15, the switching portion 16, the electrode driving portion 18,the liquid crystal display panel 19, the path 20 for bypassing the FRCportion 10, and a memory 21 on the path 20. The switching portion 16 isdisposed on the previous stage of the FRC portion 10 and switches theinput image signal to input whether to the FRC portion 10 or to the path20 in accordance with the instruction from the controlling portion 15.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 shifts the switching portion 16 to thepath 20 to bypass the FRC portion 10 and to accumulate the input imagesignal in the memory 21. The frame insert processing is subsequentlyperformed by repeatedly reading the same frame from the memory 21 morethan once. If the genre determining portion 14 determines that the inputimage signal is an image signal of a genre other than the “movie” or“animation/special effects” genre, the switching portion 16 is switchedto the FRC portion 10 to perform the FRC processing (motion-compensatedframe interpolation processing) for the input image signal. Theswitching portion 16 may be disposed on the subsequent stage of the FRCportion 10 such that the output signal of the FRC portion 10 and theoutput signal of the memory 21 are switched over to output to the liquidcrystal display panel 19.

In this embodiment, the drive frequency of the liquid crystal displaypanel 19 is not changed and is maintained at 120 Hz. If the image signalof the “movie” or “animation/special effects” genre is input, thecontrolling portion 15 and the memory 22 comprise a means for insertingan image signal of the previous or subsequent frame between the framesof the input image signal to convert the number of frames of the inputimage signal. The frame rate (the number of frames) of the display imagesignal input to the electrode driving portion 18 is always the same.

FIG. 12 is a view of a relationship between input data and output dataaccording to the fourth embodiment of the present invention. FIG. 12(A)shows the input data to the path 20 and FIG. 12(B) shows the output datafrom the path 20. As shown in FIG. 12(A), if the input image signal(input data) is input to the path 20 with a frame frequency of 60 Hz,the display time per frame is about 16.7 ms. The input data aretemporarily accumulated in the memory 21, and an image signal of theframe (in FIG. 12, frame A) is output which is repeatedly read from thememory 21 at double speed as shown in FIG. 12(B).

The liquid crystal display panel 19 displays the output data into whichthe image signal of the same frame has been inserted, at the drivefrequency of 120 Hz. Since the number of frames is converted byrepeatedly reading the same frame twice, the display time per frame isabout 8.3 ms in this case.

When the moving image such as movie or animation likely to include aplurality of the same consecutive images is input, the detection errors,the motion compensation errors, etc., of the motion vector due to thediscontinuity of images are eliminated and the image quality mayeffectively be prevented from deteriorating due to themotion-compensated FRC processing by not performing the interpolationprocessing through motion compensation for the input image signal. Sincethe frame rate is converted by repeatedly reading the same frame in thiscase, the drive frequency of the liquid crystal display panel 19 doesnot need to be changed.

In a fifth embodiment of the present invention, a path is provided tobypass the FRC portion 10 and, when the input image signal is an imagesignal of a certain genre, for example, movie or animation, the inputimage signal is input to the bypass and the input image signal is inputto a linear interpolation processing portion on the path to interpolatean image signal to which the linear interpolation has been performed. Ifthe image signal of contents of a certain predetermined genre is input,the switching is performed such that the frame rate is converted byperforming the linear interpolation processing rather than theinterpolation processing through motion compensation.

FIG. 13 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to the fifth embodiment ofthe present invention and the liquid crystal displaying device includesthe FRC portion 10, the genre determining portion 14, the controllingportion 15, the switching portion 16, the electrode driving portion 18,the liquid crystal display panel 19, the path 20 for bypassing the FRCportion 10, and a linear interpolation processing portion 22 on the path20. The switching portion 16 is disposed on the previous stage of theFRC portion 10 and switches the input image signal to input whether tothe FRC portion 10 or to the path 20 in accordance with the instructionfrom the controlling portion 15.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 shifts the switching portion 16 to thepath 20 to bypass the FRC portion 10 and the input image signal is inputto the linear interpolation processing portion 22. The linearinterpolation processing portion 22 inserts an interpolating frame towhich the linear interpolation processing has been given between frames.If the genre determining portion 14 determines that the input imagesignal is an image signal of a genre other than the “movie” or“animation/special effects” genre, the switching portion 16 is switchedto the FRC portion 10 to perform the FRC processing (motion-compensatedframe interpolation processing) for the input image signal. Theswitching portion 16 may be disposed on the subsequent stage of the FRCportion 10 such that the output signal of the FRC portion 10 and theoutput signal of the linear interpolation processing portion 22 areswitched over to output to the liquid crystal display panel 19.

In this embodiment, the drive frequency of the liquid crystal displaypanel 19 is not changed and is maintained at 120 Hz. The frame rate (thenumber of frames) of the display image signal input to the electrodedriving portion 18 is always the same. If the image signal of the“movie” or “animation/special effects” genre is input, the linearinterpolation processing portion 22 comprises a means for interpolatingan image signal to which the linear interpolation processing has beengiven between the frames of the input image signal to convert the numberof frames of the input image signal. In the linear interpolationprocessing, as described in the above document (Yamauchi Tatsuro, “TVStandards Conversion”, Journal of the Institute of Television Engineersof Japan, Vol. 45, No. 12, pp. 1534-1543 (1991)), an interpolating frameis acquired through linear interpolation using a frame interpolationratio α from the signal of the previous frame and the signal of thecurrent frame.

FIG. 14 is a view of a relationship between input data and output dataaccording to the fifth embodiment of the present invention. FIG. 14(A)shows the input data to the path 20 and FIG. 14(B) shows the output datafrom the path 20. As shown in FIG. 14(A), if the input image signal(input data) is input to the path 20 with a frame frequency of 60 Hz,the display time per frame is about 16.7 ms. The input data are input tothe linear interpolation processing portion 22, and the image signal towhich the linear interpolation processing has been given (in FIG. 14,frame A+B) is interpolated and output between the frames (in this case,between frames A and B) as shown in FIG. 14(B).

The liquid crystal display panel 19 displays the output data into whichthe image signal to which the linear interpolation processing has beengiven, is interpolated at the drive frequency of 120 Hz. Since thenumber of frames is converted by interpolating the image signal to whichthe linear interpolation processing has been given, the display time perframe is about 8.3 ms in this case.

When the moving image such as movie or animation likely to include aplurality of the same consecutive images is input, the detection errors,the motion compensation errors, etc., of the motion vector due to thediscontinuity of images are eliminated and the image quality mayeffectively be prevented from deteriorating due to themotion-compensated FRC processing by not performing the interpolationprocessing through motion compensation for the input image signal. Sincethe frame rate is converted by interpolating the image signal to whichthe linear interpolation processing has been given in this case, thedrive frequency of the liquid crystal display panel 19 does not need tobe changed.

In a sixth embodiment of the present invention, a path is provided tobypass the FRC portion 10 and, when the input image signal is an imagesignal of a certain genre, for example, movie or animation, the inputimage signal is input to the bypass path and the input image signal isinput to a black-level signal insert processing portion on the path toinsert a predetermined monochromatic image signal such as a black-levelsignal. If the image signal of contents of a certain predetermined genreis input, the switching is performed such that the frame rate isconverted by performing the monochromatic image insertion processingrather than the interpolation processing through motion compensation.

FIG. 15 is a block diagram of an exemplary main configuration of aliquid crystal displaying device according to the sixth embodiment ofthe present invention and the liquid crystal displaying device includesthe FRC portion 10, the genre determining portion 14, the controllingportion 15, the switching portion 16, the electrode driving portion 18,the liquid crystal display panel 19, the path 20 for bypassing the FRCportion 10, and a black-level signal insert processing portion 23 on thepath 20. The switching portion 16 is disposed on the previous stage ofthe FRC portion 10 and switches the input image signal to input whetherto the FRC portion 10 or to the path 20 in accordance with theinstruction from the controlling portion 15.

If the genre determining portion 14 determines that the input imagesignal is an image signal of the “movie” or “animation/special effects”genre, the controlling portion 15 shifts the switching portion 16 to thepath 20 to bypass the FRC portion 10 and the input image signal is inputto the black-level signal insertion processing portion 23. Theblack-level signal insertion processing portion 23 performs the timescale compression (frame rate conversion) for the input image signal,for example, with the use of a memory to insert the predeterminedmonochromatic image signal such as a black-level signal between theinput frames. If the genre determining portion 14 determines that theinput image signal is an image signal of a genre other than the “movie”or “animation/special effects” genre, the switching portion 16 isshifted to the FRC portion 10 to perform the FRC processing(motion-compensated frame interpolation processing) for the input imagesignal. The switching portion 16 may be disposed on the subsequent stageof the FRC portion 10 such that the output signal of the FRC portion 10and the output signal of the black-level signal insert processingportion 23 are switched over to output to the liquid crystal displaypanel 19.

In this embodiment, the drive frequency of the liquid crystal displaypanel 19 is not changed and is maintained at 120 Hz. The frame rate (thenumber of frames) of the display image signal input to the electrodedriving portion 18 is always the same. If the image signal of the“movie” or “animation/special effects” genre is input, the black-levelsignal insertion processing portion 23 comprises a means for insertingthe predetermined monochromatic image signal such as a black-levelsignal between the frames of the input image signal to convert thenumber of frames of the input image signal. Another embodiment of theblack-level signal insertion processing may be configured such that theelectrode driving portion 18 applies a voltage for writing black to theliquid crystal display panel 19 for a predetermined period (in the caseof this example, 1/120 second).

FIG. 16 is a view of a relationship between input data and output dataaccording to the sixth embodiment of the present invention. FIG. 16(A)shows the input data to the path 20 and FIG. 16(B) shows the output datafrom the path 20. As shown in FIG. 16(A), if the input image signal(input data) is input to the path 20 with a frame frequency of 60 Hz,the display time per frame is about 16.7 ms. The input data are input tothe black-level signal insertion processing portion 23, and ablack-level signal (in FIG. 16, black-colored frame) is inserted andoutput between the frames (in this case, between the frames A and B) asshown in FIG. 16(B).

Although the image quality deterioration due to the motion blur isimproved and the image quality deterioration due to the motioncompensation error is not generated by inserting the black image signalbetween the frames of the input image signal in this way, the emissionluminance must be increased in a backlight (not shown) disposed on thebackside of the liquid crystal display panel 19 to compensate thereduction of the display luminance due to the shortening of the imagedisplay period.

The liquid crystal display panel 19 displays the output data, into whichthe black-level signal has been inserted, at the drive frequency of 120Hz. Since the number of frames is converted by inserting the black-levelsignal, the display time per frame is about 8.3 ms in this case.

When a moving image such as movie or animation likely to include aplurality of the same consecutive images is input, the detection errors,the motion compensation errors, etc., of the motion vector due to thediscontinuity of images are eliminated and the image quality mayeffectively be prevented from deteriorating due to themotion-compensated FRC processing by not performing the interpolationprocessing through motion compensation for the input image signal. Sincethe frame rate is converted by inserting the monochromatic image signalin this case, the drive frequency of the liquid crystal display panel 19does not need to be changed. The moving image quality improving effectmay also be maintained in this case.

Other than the above embodiment, when the input image signal is an imagesignal of a certain genre, for example, movie or animation, the imagequality may be prevented from deteriorating due to themotion-compensated FRC processing and the moving image quality improvingeffect may be maintained at the same time by dividing the original imageof the input frame into a plurality of frame images at a predeterminedluminance ratio for the frame rate conversion.

In a seventh embodiment of the present invention, when the input imagesignal is an image signal of a certain genre, for example, movie oranimation, the compensation intensity of the motion compensationprocessing may be varied in the interpolating frame generating portion.Specifically, the weighted addition rate may be varied when thepull-down converted image signal is input by providing the interpolatingframe generating portion that performs weighted addition of the imagesignal to which the motion compensation processing has been given andthe image signal to which the linear interpolation processing has beengiven at a predetermined rate to generate an interpolating frame.

FIG. 17 is a block diagram of an exemplary main configuration of the FRCportion 10 according to the seventh embodiment of the present invention,and the frame generating portion 12 of the FRC portion 10 includes theinterpolating frame memory 12 a, the interpolating frame generatingportion 12 b, and a compensation intensity varying portion 12 e that mayvary the compensation intensity of the motion compensation processing inthe FRC portion 10. In FIG. 17, V denotes an interpolating vector; αdenotes a frame interpolation ratio; and β denotes interpolationintensity (weighted addition rate).

Generally, for example, the frame interpolation through the linearinterpolation between two frames and the frame interpolation usingmotion vectors (motion compensated interpolation)are known as methods ofthe frame interpolation processing. In the former case, an interpolatingframe is acquired by the linear interpolation from the signal of theprevious frame and the signal of the current frame at a frameinterpolation ratio α. Therefore, using this linear interpolation mayprevent the image quality deterioration due to the motion compensationerrors in the FRC processing.

On the other hand, to acquire an interpolating frame from the previousframe and the current frame in the latter case, the interpolating vectorV is detected from the motion vectors between the previous frame imageand the current frame image, and the interpolating frame is acquiredfrom the weighted addition of a signal of the previous frame imageshifted by a degree of αV obtained by dividing the value (interpolatingvector V) by the frame interpolation ratio α and a signal of the currentframe image shifted by (1−α)V. Although good image quality may beacquired without deteriorating the resolution since a moving imageitself is captured and compensated by using this motion-compensatedinterpolation, the image quality may be deteriorated in the pulled-downvideo due to this processing.

Therefore, in this embodiment, the compensation intensity varyingportion 12 e is disposed in the frame generating portion 12. If thegenre determining portion 14 determines that the input image signal isan image signal of the “movie” or “animation/special effects” genre, thecompensation intensity varying portion 12 e varies the weighted additionrate β. The weighted addition rate β is a rate for performing theweighted addition of the image signal to which the motion compensationprocessing has been given and the image signal to which the linearinterpolation processing has been given. The interpolating framegenerating portion 12 b of this embodiment performs the weightedaddition of the linear interpolation and the motion-compensatedinterpolation in accordance with the weighted addition rate β togenerate the interpolating frame.

For example, if the input image signal is an image signal of contents ofthe “movie” or “animation/special effects” genre, the compensationintensity varying portion 12 e sets the weighted addition rate β=0 anddefines the image signal to which the linear interpolation processinghas been given as the interpolating frame to prevent the imagedeterioration. On the other hand, if the input image signal is an imagesignal of contents of a genre other than the “movie” or“animation/special effects” genre, the weighted addition rate β=1 is setto define the image signal to which the motion compensation processinghas been given as the interpolating frame to achieve better imagequality for the moving image.

Since the weighted addition rate β may arbitrarily and variably be set,the rate may be set to a substantially intermediate value between zeroand one. This enables to control the deterioration of the image qualityand to perform the motion compensation in the interpolating frame imageat the same time, and this may appropriately improve both the imagequality deterioration due to the motion blur and the image qualitydeterioration due to the motion compensation errors.

Since the compensation intensity may be varied (weakened) in the motioncompensation processing in the FRC when the moving image such as movieor animation likely to include a plurality of the same consecutiveimages is input, the image quality deterioration due to themotion-compensated FRC process may effectively be controlled by reducingthe effects of the detection errors, the motion compensation errors,etc., of the motion vector due to the discontinuity of images.

FIG. 18 is a flowchart for explaining an example of an image displayingmethod by the image displaying device of the present invention. Anexample of the image displaying method in the first embodiment will bedescribed. First, the image displaying device determines whether acontent type (genre) of the input image signal is “movie” based on theacquired genre information (step S1), and if it is determined that thetype is “movie” (in the case of YES), the motion vector or theinterpolating vector is set to zero-vector to make the motioncompensation processing of the FRC portion 10 ineffective (step S2). Ifit is determined at step S1 that the content type (genre) of the inputimage signal is not “movie” (in the case of NO), it is determinedwhether the content type (genre) of the input image signal is“animation/special effects” (step S3).

If it is determined at step S3 that the type is “animation/specialeffects” (in the case of YES), the motion vector or the interpolatingvector is set to zero-vector to make the motion compensation processingof the FRC portion 10 ineffective (step S2), and if it is determinedthat the type is not “animation/special effects” (in the case of NO),the motion compensation processing of the FRC portion 10 is executed asusual (step S4). The image signal with the frame frequency converted inthis way is displayed and output from the liquid crystal display panel19 (step S5).

FIG. 19 is a flowchart for explaining another example of the imagedisplaying method by the image displaying device of the presentinvention. An example of the image displaying method in the second tosixth embodiments will be described. First, the image displaying devicedetermines whether the content type (genre) of the input image signal is“movie” based on the acquired genre information (step S11), and if it isdetermined that the type is “movie” (in the case of YES), themotion-compensated frame interpolation processing of the FRC portion 10is bypassed and the input image signal is input to the other path 20(step S12).

On the bypassing path 20, the image signal is output after the framerate is converted by executing any one of the inter-frame interpolationof the image signal to which the linear interpolation processing hasbeen given, the inter-frame interpolation of the image signal of thesame frame, and the inter-frame interpolation of the predeterminedmonochromatic image signal such as a black-level signal, or the inputimage signal is directly output to execute processing such as changingthe drive frequency of the liquid crystal display panel 19.

If it is determined at step S11 that the content type (genre) of theinput image signal is not “movie” (in the case of NO), it is determinedwhether the content type (genre) of the input image signal is“animation/special effects” (step S13). If it is determined at step S13that the type is “animation/special effects” (in the case of YES), themotion-compensated frame interpolation processing of the FRC portion 10is bypassed and the input image signal is input to the other path 20(step S12), and the image signal is output after the frame rate isconverted by executing any one of the inter-frame interpolation of theimage signal to which the linear interpolation processing has beengiven, the inter-frame interpolation of the image signal of the sameframe, and the inter-frame interpolation of the predeterminedmonochromatic image signal such as a black-level signal, or the inputimage signal is directly output to execute processing such as changingthe drive frequency of the liquid crystal display panel 19. If it isdetermined at step S13 that the type is not “animation/special effects”(in the case of NO), the image signal is output that is given themotion-compensated interpolation processing of the FRC portion 10 (stepS14). Finally, the image is displayed and output from the liquid crystaldisplay panel 19 (step S15).

FIG. 20 is a flowchart for explaining another example of the imagedisplaying method by the image displaying device of the presentinvention. An example of the image displaying method in the seventhembodiment will be described. First, the image displaying devicedetermines whether the content type (genre) of the input image signal is“movie” based on the acquired genre information (step S21), and if it isdetermined that the type is “movie” (in the case of YES), thecompensation intensity is varied (weakened) in the motion compensationprocessing of the FRC portion 10 (step S22). If it is determined at stepS21 that the content type (genre) of the input image signal is not“movie” (in the case of NO), it is determined whether the content type(genre) of the input image signal is “animation/special effects” (stepS23).

If it is determined at step S23 that the type is “animation/specialeffects” (in the case of YES), the compensation intensity is varied(weakened) in the motion compensation processing of the FRC portion 10(step S22). If it is determined at step S23 that the type is not“animation/special effects” (in the case of NO), the compensationintensity is increased as usual in the motion compensation processing ofthe FRC portion 10 (step S24). The image signal with the frame frequencyconverted in this way is displayed and output from the liquid crystaldisplay panel 19 (step S25).

According to the present invention, if the image signal such as movie oranimation likely to include a plurality of the same consecutive imagesbecause of the 2-3 pull-down conversion or the 2-2 pull-down conversionis input, display and output may be performed by making the motioncompensation processing in the frame rate converting (FRC) portionineffective display and output and, therefore, the image quality mayeffectively be prevented from deteriorating due to the motioncompensation errors. It is needless to say that the image signal is notlimited to the television image signal and may be an image signalreproduced from an external medium.

Although the motion compensation processing of the frame rate converting(FRC) portion is controlled in accordance with the major categories ofthe genre codes defined in the digital broadcasting standard in thedescription of the above embodiments, finer and more effective controlmay be performed in accordance with the middle categories or minorcategories of the genre codes.

Although the exemplary embodiments related to the image processingdevice and method of the present invention have been described as above,the above description will facilitate understanding of an imageprocessing program operable to drive a computer to execute the imageprocessing method as a program and a program recording medium, which isa computer-readable recording medium having the image processing programrecorded thereon.

Although the image processing device of the present invention isintegrally disposed within the image displaying device in the formdescribed in the above embodiments, the image processing device of thepresent invention is not limited to this form and it is needless to saythat the image processing device may be disposed in video output devicessuch as various recording medium reproducing devices, for example.

1-41. (canceled)
 42. An image displaying device having a rate convertingportion that interpolates an interpolation image signal between framesor fields of an input image signal to convert the number of frames orfields of the input image signal, wherein a determining portion thatdetermines a content genre the input image signal belongs to based ongenre information acquired from broadcast data, a medium, or a networkis included and the rate converting portion includes an interpolationimage generating portion that applies a motion compensation processingto the input image signal to generate an interpolation image signalbased on motion vector information between frames or fields of the inputimage signal, and the image signal generated by applying the motioncompensation processing is not interpolated when the genre determined bythe determining portion is a certain genre including a moving imagepotentially having the same consecutive images in a plurality of framesor fields.
 43. An image displaying device as defined in claim 42,wherein the rate converting portion interpolates an image signalgenerated by disabling the motion compensation processing of theinterpolation image generating portion between frames or fields of theinput image signal when the genre determined by the determining portionis the certain genre.
 44. An image displaying device as defined in claim43, wherein the interpolation image generating portion includes a motionvector detecting portion that detects the motion vector informationbetween consecutive frames or fields included in the input image signal,and an interpolating vector allocating portion that allocates aninterpolating vector between the frames or the fields based on thedetected motion vector information.
 45. An image displaying device asdefined in 44, wherein the interpolation image generating portion setsthe motion vector detected by the motion vector detecting portion tozero-vector to make the motion compensation processing ineffective whenthe genre determined by the determining portion is the certain genre.46. An image displaying device as defined in claim 44, wherein theinterpolation image generating portion sets the interpolating vectorallocated by the interpolating vector allocating portion to zero-vectorto make the motion compensation processing ineffective when the genredetermined by the determining portion is the certain genre.
 47. An imagedisplaying device as defined in claim 42, wherein the image displayingdevice does not insert the interpolation image signal generated byapplying the motion compensation processing between frames or fields ofthe input image signal and does not convert the number of frames orfields of the input image signal when the genre determined by thedetermining portion is the certain genre.
 48. An image displaying deviceas defined in claim 47, wherein a drive frequency of a display paneldisplaying the image signals is variable, and the image displayingdevice includes a portion for varying the drive frequency of the displaypanel from a frame frequency or a field frequency converted by the rateconverting portion to a frame frequency or a field frequency of theinput image signal when the genre determined by the determining portionis the certain genre.
 49. An image displaying device as defined in claim42, wherein the rate converting portion inserts an image signal to whichthe motion compensation processing has not been given between frames orfields of the input image signal to convert the number of frames orfields of the input image signal when the genre determined by thedetermining portion is the certain genre.
 50. An image displaying deviceas defined in claim 49, wherein the rate converting portion insertsbetween frames or fields of the input image signal an image signal ofthe frames or the fields to convert the number of frames or fields ofthe input image signal when the genre determined by the determiningportion is the certain genre.
 51. An image displaying device as definedin claim 49, wherein the rate converting portion interpolates betweenframes or fields of the input image signal an image signal acquired byapplying a linear interpolation processing to an image signal of theframes or the fields to convert the number of frames or fields of theinput image signal when the genre determined by the determining portionis the certain genre.
 52. An image displaying device as defined in claim48, wherein the rate converting portion inserts a predeterminedmonochromatic image signal between frames or fields of the input imagesignal to convert the number of frames or fields of the input imagesignal when the genre determined by the determining portion is thecertain genre.
 53. An image displaying device as defined in claim 42,wherein the certain genre is movie.
 54. An image displaying device asdefined in claim 42, wherein the certain genre is animation.
 55. Animage displaying device as defined in claim 42, wherein the determiningportion determines the genre of contents the input image signal belongsto based on electronic program information transmitted by superimposingon broadcast data.
 56. An image displaying device as defined in claim42, wherein the determining portion determines the genre of contents theinput image signal belongs to based on identification information whichis indicative of the contents and is added to a medium.
 57. An imagedisplaying device as defined in claim 42, wherein the rate convertingportion converts a frame frequency or field frequency of the input imagesignal into integral multiples of each of them.
 58. An image displayingmethod having a rate converting step of interpolating an interpolationimage signal between frames or fields of an input image signal toconvert the number of frames or fields of the input image signal,wherein the step of determining a content genre the input image signalbelongs to based on genre information acquired from broadcast data, amedium, or a network is included and the rate converting step includesan interpolation image generating step of applying a motion compensationprocessing to the input image signal to generate an interpolation imagesignal based on motion vector information between frames or fields ofthe input image signal, and the image signal generated by applying themotion compensation processing is not interpolated when the determinedgenre is a certain genre including a moving image potentially having thesame consecutive images in a plurality of frames or fields.
 59. An imagedisplaying method as defined in claim 58, wherein at the rate convertingstep, an image signal generated by making the motion compensationprocessing at the interpolation image generating step ineffective isinterpolated between frames or fields of the input image signal when thedetermined genre is the certain genre.
 60. An image displaying method asdefined in claim 58, wherein the interpolation image signal generated byapplying the motion compensation processing is not inserted betweenframes or fields of the input image signal and the number of frames orfields of the input image signal is not converted when the determinedgenre is the certain genre.
 61. An image displaying method as defined inclaim 58, wherein at the rate converting step, an image signal of theframes or the fields is inserted between frames or fields of the inputimage signal to convert the number of frames or fields of the inputimage signal when the determined genre is the certain genre.
 62. Animage displaying method as defined in claim 58, wherein at the rateconverting step, an image signal acquired by applying a linearinterpolation processing to an image signal of the frames or the fieldsis interpolated between frames or fields of the input image signal toconvert the number of frames or fields of the input image signal whenthe determined genre is the certain genre.
 63. An image displayingmethod as defined in claim 58, wherein at the rate converting step, apredetermined monochromatic image signal is inserted between frames orfields of the input image signal to convert the number of frames orfields of the input image signal when the determined genre is thecertain genre.
 64. An image processing device having a rate convertingportion that interpolates an interpolation image signal between framesor fields of an input image signal to convert the number of frames orfields of the input image signal, wherein the rate converting portionincludes an interpolation image generating portion that applies a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and the image signalgenerated by applying the motion compensation processing is notinterpolated when the genre determined by a determining portion thatdetermines a content genre the input image signal belongs to based ongenre information acquired from broadcast data, a medium, or a networkis a certain genre potentially including an image signal having the sameconsecutive images in a plurality of frames or fields.
 65. An imageprocessing device as defined in claim 64, wherein the rate convertingportion interpolates an image signal generated by making the motioncompensation processing of the interpolation image generating portionineffective between frames or fields of the input image signal when thegenre determined by the determining portion is the certain genre.
 66. Animage processing device as defined in claim 64, wherein the rateconverting portion inserts an image signal to which the motioncompensation processing has not been given between frames or fields ofthe input image signal to convert the number of frames or fields of theinput image signal when the genre determined by the determining portionis the certain genre.
 67. An image processing method having a rateconverting step of interpolating an interpolation image signal betweenframes or fields of an input image signal to convert the number offrames or fields of the input image signal, wherein the step ofdetermining a content genre the input image signal belongs to based ongenre information acquired from broadcast data, a medium, or a networkis included and the rate converting step includes an interpolation imagegenerating step of applying a motion compensation processing to theinput image signal to generate an interpolation image signal based onmotion vector information between frames or fields of the input imagesignal, and the image signal generated by applying the motioncompensation processing is not interpolated when the determined genre isa certain genre including a moving image potentially having the sameconsecutive images in a plurality of frames or fields.
 68. Ali imagedisplaying method as defined in claim 67, wherein at the rate convertingstep, an image signal generated by making the motion compensationprocessing at the interpolation image generating step ineffective isinterpolated between frames or fields of the input image signal when thedetermined genre is the certain genre.
 69. An image displaying method asdefined in claim 67, wherein at the rate converting step, an imagesignal of the frames or the fields is inserted between frames or fieldsof the input image signal to convert the number of frames or fields ofthe input image signal when the determined genre is the certain genre.70. An image displaying method as defined in claim 67, wherein at therate converting step, an image signal acquired by applying a linearinterpolation processing to an image signal of the frames or the fieldsis interpolated between frames or fields of the input image signal toconvert the number of frames or fields of the input image signal whenthe determined genre is the certain genre.
 71. An image displayingmethod as defined in claim 67, wherein at the rate converting step, apredetermined monochromatic image signal is inserted between frames orfields of the input image signal to convert the number of frames orfields of the input image signal when the determined genre is thecertain genre.
 72. An image displaying device having a rate convertingportion that interpolates an interpolation image signal between framesor fields of an input image signal to convert the number of frames orfields of the input image signal, wherein a determining portion thatdetermines a content genre the input image signal belongs to based ongenre information acquired from broadcast data, a medium, or a networkis included and the rate converting portion includes an interpolationimage generating portion that applies a motion compensation processingto the input image signal to generate an interpolation image signalbased on motion vector information between frames or fields of the inputimage signal, and the interpolation image signal generated by reducing acompensation intensity of the motion compensation processing isinterpolated between frames or fields of the input image signal when thegenre determined by the determining portion is a certain genre includesa moving image potentially having the same consecutive images in aplurality of frames or fields.
 73. An image displaying device as definedin claim 72, wherein the interpolation image generating portion performsweighted addition of an image signal to which the motion compensationprocessing has been given and an image signal to which the motioncompensation processing has not been given at a predetermined rate togenerate an interpolation image signal, and the weighted addition rateis varied when the genre determined by the determining portion is thecertain genre.
 74. An image displaying device as defined in claim 73,wherein the interpolation image generating portion uses the image signalto which the motion compensation processing has not been given for theinterpolation image signal when the genre determined by the determiningportion is the certain genre and uses the image signal to which themotion compensation processing has been given for the interpolationimage signal when the genre determined by the determining portion is notthe certain genre.
 75. An image displaying device as defined in claim73, wherein the interpolation image generating portion uses an imagesignal to which a linear interpolation processing has been given betweenframes or fields of the input image signal as the image signal to whichthe motion compensation processing has not been given.
 76. An imagedisplaying device as defined in claim 73, wherein the certain genre ismovie.
 77. An image displaying device as defined in claim 73, whereinthe certain genre is animation.
 78. An image displaying device asdefined in claim 73, wherein the determining portion determines thegenre of contents the input image signal belongs to based on electronicprogram information transmitted by superimposing on broadcast data. 79.An image displaying device as defined in claim 73, wherein thedetermining portion determines the genre of contents the input imagesignal belongs to based on identification information which isindicative of the contents and is added to a medium.
 80. An imagedisplaying method having a rate converting step of interpolating aninterpolation image signal between frames or fields of an input imagesignal to convert the number of frames or fields of the input imagesignal, wherein the step of determining a content genre the input imagesignal belongs to based on genre information acquired from broadcastdata, a medium, or a network is included and the rate converting stepincludes an interpolation image generating step of applying a motioncompensation processing to the input image signal to generate aninterpolation image signal based on motion vector information betweenframes or fields of the input image signal, and an interpolation imagesignal generated by reducing a compensation intensity of the motioncompensation processing is interpolated between frames or fields of theinput image signal when the determined genre is a certain genreincluding a moving image potentially having the same consecutive imagesin a plurality of frames or fields.
 81. An image processing devicehaving a rate converting portion that interpolates an interpolationimage signal between frames or fields of an input image signal toconvert the number of frames or fields of the input image signal,wherein the rate converting portion includes an interpolation imagegenerating portion that applies a motion compensation processing to theinput image signal to generate an interpolation image signal based onmotion vector information between frames or fields of the input imagesignal, and the interpolation image signal generated by reducing acompensation intensity of the motion compensation processing isinterpolated between frames or fields of the input image signal when thegenre determined by a determining portion that determines a contentgenre the input image signal belongs to based on genre informationacquired from broadcast data, a medium, or a network is a certain genreincluding a moving image potentially having the same consecutive imagesin a plurality of frames or fields.
 82. An image processing methodhaving a rate converting step of interpolating an interpolation imagesignal between frames or fields of an input image signal to convert thenumber of frames or fields of the input image signal, wherein the stepof determining a content genre the input image signal belongs to basedon genre information acquired from broadcast data, a medium, or anetwork is included and the rate converting step includes aninterpolation image generating step of applying a motion compensationprocessing to the input image signal to generate an interpolation imagesignal based on motion vector information between frames or fields ofthe input image signal, and an interpolation image signal generated byreducing a compensation intensity of the motion compensation processingis interpolated between frames or fields of the input image signal whenthe determined genre is a certain genre including a moving imagepotentially having the same consecutive images in a plurality of framesor fields.